Metal ribbon stator and motor comprising same

ABSTRACT

A stator made from a ribbon of metal having multiple layers of slit metal, and motors made therefrom are described. A ribbon having multiple layers of metal is formed into a stator such as by flattening or pleating the ribbon to form each pole of a stator having a plurality of stator teeth, or poles. The stator formed from the metal ribbon may be configured into any suitable type of motor, such as an axial transverse flu motor. A magnetic flu return may also be made out of metal ribbon.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of, and claims the benefit of andpriority to, U.S. Ser. No. 14/758,887, entitled Metal Ribbon Stator andMotor Comprising Same, filed on Jul. 1, 2015 and currently pending,which is a U.S. national phase filing under 35 U.S.C. §371 of, andclaims the benefit of and priority to, PCT Application No.PCT/US2014/000004, entitled Metal Ribbon Stator and Motor ComprisingSame and filed on Jan. 6, 2014, which claims the benefit of U.S.Provisional Patent Application No. 61/848,457, entitled Ribbon Statorand Motor Comprising Same and filed on Jan. 4, 2013, the entirety bothapplications are incorporated by reference herein.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to stators for electric motors, and inparticular stators comprising a multilayer amorphous ribbon

Background

The present invention is an axial transverse flux motor providing hightorque density, low cost construction and providing for high RPMoperation b allowing for use of materials that do not require stampingfor assembly. The design uses non-oriented and flux conduction materialin a “ribbon” or “tape”, typically formed by Mining. For lower RPMoperation, silicon steel works well. For higher RPM operation, amorphousmetal is a good material of choice in that it has high permeability andlow loss at both low and high frequency applications. Amorphous metal,such as Metglass available from Metglas Inc, Conway SC or AT & M,Beijing China, or Nanocrystalline materials are very difficult tomachine or form into shapes suitable for stator configurations

There exists a need for a motor/generator stator made from materialallowing for as range of non-oriented slit materials including siliconsteel, amorphous metal, and Nanocrystalline materials that is alsosimple to assembly, high in torque density, allows Ku tight tolerances,requires very few parts, thereby reducing assembly cost and thepotential for parts being incorrectly assemble or positioned. Thereexists a need for a motor that has low loss at low and high rotationalfrequency, and especially motors with high pole counts, such astransverse flux motors.

SUMMARY OF THE INVENTION

This invention relates to an axial transverse flux motor/generator hereafter referred to as an AFTM motor. The pole pieces of thearmature/stator of the motor are principally made from a ribbon or tapeof slit magnetically conductive materials hereafter referred to as atape. The tape is formed of layers of suitable magnetically conductivematerial such as silicon steel, amorphous metal, and nanocrystallinematerial.

The tape is formed of multiple layers of material, typically by windinginto a toroid. In a first configuration, toroids are then flattened intobars fanning, as pole piece with at least one end remaining uncut toallow flux, to travel around the end interacting with the magnet ring.In another configurations two or more poles may be formed from onetoroid. These may be formed by folding or “pleating” to farm theplurality of armature teeth.

The tape has a top surface and bottom surface, a first edge and a secondedge. The tape formed pole or pole set may be positioned with the polesadjacent a rotor with the metal tape edge facing the magnet ring. Themagnet ring shown here is formed of an assembly of magnets with fluxconcentrators placed between them. There may be rotating or stationaryhowever for easy of discussion, will be referred to hereafter as therotor. The flux that has entered the edges of pole or pole set travelssubstantially along the layers without crossing layers to a return part.The return part may mal also be formed of a toroid in tape or anothermaterial such as SMC. The flux then passes substantially axially to thepaired pole or pole set surrounding the coil. The flux travels againthrough the edge of the pole or pole set substantially in plane to therotor.

The pole or pole sets formed of tape maybe farmed such that as gap isleft so that flux will have a greater tendency to stay in the planes ofthe tape. The individual layers of the ribbon may be adhered in discretelocations, such as by the application of a discrete amount of adhesivebetween two ribbon layers. In another embodiment, a discontinuousadhesive may be applied to one or more surfaces of a ribbon layer duringthe formation of the ribbon loop or tape. An adhesive may be a magneticflux insulator or magnetic flux conductor and may provide a small gapbetween ribbon layers. In still another embodiment, a magnetic insulatormay be configured between two or more of the formed stator teeth.

The poles or pole sets or otherwise formed tape may be position aroundat least a portion of a rotor as at stator stack. A stator stack mayextend around any suitable portion of the rotor including, but notlimited to, 30 electrical degrees or more, 50 electrical degrees or more120 electrical degrees or more 180 electrical degrees or more, 360electrical degrees or more and any range between and including thevalues provided. In an exemplary embodiment, a motor comprises threestator halves configured fir approximately 120 electrical degrees oneach side of the rotor forming 3 phases in a plane.

An electric motor as described herein may comprise a rotor configuredbetween a first stator half and a second stator half. The rotor may beany suitable type of rotor including, but not limited to, a permanentmagnet (PM) rotor, an alternating field rotor, a PM flux concentratortype rotor, a wound field rotor, an induction rotor, and a low loss PMflux concentrating type rotor.

A stator can he made using a tape, as described herein, in a very costeffective an efficient manner. Slitting materials provides for very hightolerances and when a slit material is formed into a tape that is usedto form a stator, the adherence to tight tolerances is greatlysimplified. In addition, slitting magnetically conducting materials,such as amorphous metal, is cost effective, as it requires no additionaltooling to stamping, does not remove and waste the material and allowsfor high tolerances. Amorphous metals and other low magnetic lossmaterials are expensive and slitting to form a ribbon provides forextremely high utilization of the material. Furthermore, a stator can bemade with only three components, a first stator half, a second statorhalf and a return. Since all three of these components can be made fromhigh precision slit materials, the tolerances of the assembly can beheld to very high levels. A tape formed of a plurality of ribbonsprovides for high mechanical strength in the axial direction. The tapemay be easily formed, bent folded, pleated and shaped in the radialdirection but is extremely stiff in the axial direction. Therefore,stator teeth can be easily formed without compromising the strength ofthe stator in the axial direction.

A stator tooth may comprise shaped tape, as described herein, and thetape may he pressed into a single pole piece or folded to form number ofpole pieces to any suitable degree, such as 180 degrees, or completelyback upon itself, or any other suitable degree. As mentioned above, agap may be left so the fold in not closed and flux passing betweenplanes may be reduced, in some embodiments, a tape is folded back uponitself and the inside surfaces touch and/or are adhered together.

The summary of the invention is provided as a general introduction tosonic of the embodiments of the invention, and is not intended to belimiting. It is to be understood that various features andconfigurations of features described in the Summary may be combined inany suitable way to form any number of embodiments of the invention.Some additional example embodiments including variations and alternativeconfigurations of the invention are provided herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention, andtogether with the description serve to explain the principles of theinvention.

FIG. 1 shows an isometric view of a portion a simplified exemplaryin-plane three-phase axial transverse flux motor having tape statorhalves configured on either side of a rotor.

FIG. 2 shows a side view the exemplary simplified axial transverse fluxmotor shown in FIG. 1,

FIG. 3 shows a cross-sectional view of exemplary axial transverse fluxmotor shown in FIG. 2.

FIG. 4A shows a side view of an exemplary tape having a plurality ofribbon layers.

FIG. 4B shows as side view of an exemplary tape having a plurality ofribbon layers and a space between ribbon layers.

FIG. 5 shows a side view of an exemplary ribbon.

FIG. 6 shows a side view of an exemplary tape loop configured on a core.

FIG. 7A shows a side view of an exemplary tape loop,

FIG. 7B shows a side view of an exemplary tape loop compressed,

FIG. 8 shows a side view of an exemplary simplified tape formed into astator having a plurality of stator teeth formed from the tape.

FIG. 9 shows a site view of an exemplary tape formed into a statorhaving a plurality of stator teeth formed from the pleated tape.

FIG. 10 shows a side view of an exemplary tape formed into a statorhaving a plurality of stator teeth formed from the pleated tape.

FIG. 11 shows an isometric view of a portion an exemplary transverseflux motor having stator halves formed from tape and configured oneither side of a rotor and showing angled teeth to allow for wire exitswithout loss of flux and shortened copper loop shape.

FIG. 12 shows an isometric exploded view of a portion an exemplaryin-plane three-phase transverse flux motor having stator halves formedfrom tape and configured on either side of a rotor with angled statorteeth portions and shortened coil path.

FIG. 13 shows a side view of a portion an exemplary asymmetrictransverse flux motor having three stator halves formed from tape andcoil entry ends.

FIG. 14 shows a side view of an exemplary stator half consisting offormed tape, and a return and showing angled teeth to allow for coil andwire exit without reducing flux area.

FIG. 15 shows an isometric view of a portion an exemplary doublein-plane three-phase transverse flux motor having tape stator halvesconfigured on either side of a rotor of two rotors.

FIG. 16 shows an isometric view of a portion an exemplary axiallystacked three-phase transverse flux motor having tape stator halvesconfigured on either side of a rotor of three rotors.

FIG. 17 shows an isometric view of a portion an exemplary single phasetransverse flux motor having a tape stator half configured on eitherside of a rotor.

FIG. 18 shows an isometric view of a portion an exemplary single phasetransverse flux motor having a discrete teeth on either side of thestator.

FIG. 19 shows an isometric view of an exemplary three phase axialtransverse flux motor having, discrete stator tooth and flux sharingbetween phases.

FIG. 20 a graph of the resulting electrical output from the motor shownin FIG. 19.

FIG. 21 shows data used to produce the graph shown in FIG. 20.

Corresponding reference characters indicate corresponding partsthroughout the several views of the figures. The figures represent anillustration of some of the embodiments of the present invention and arenot to be construed as limiting the scope of the invention in anymanner. Further, the figures are not necessarily to scale, some featuresmay be exaggerated to show details of particular components. Therefore,specific structural and functional details disclosed herein are not tobe interpreted as limiting, but merely as a representative basis forteaching one skilled in the art to variously employ the presentinvention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

As used herein, the terms “comprises,” “comprising,” “includes,”“including.,” “has,” “having” or any other variation thereof, areintended to cover a non-exclusive inclusion. For example, a process,method, article, or apparatus that comprises a list of elements is notnecessarily limited to only those elements but may include otherelements not expressly listed or inherent to such process, method,article, or apparatus. Also, use of “a” or “an” are employed to describeelements and components described herein. This is done merely forconvenience and to give a general sense of the scope of the invention.This description should be read to include one or at least one and thesingular also includes the plural unless it is obvious that if is meantotherwise,

Certain exemplary embodiments of the present invention are describedherein and illustrated in the accompanying figures. The embodimentsdescribed are only for purposes of illustrating the present inventionand should not be interpreted as limiting the scope of the invention.Other embodiments of the invention, and certain modifications,combinations and improvements of the described embodiments, will occurto those skilled in the art and all such alternate embodiments,combinations, modifications, improvements are within the scope of thepresent invention.

FIG. 1 shows an isometric view of a portion an exemplary simplifiedin-plane three phase transverse flux motor 70 having stator 12 halvesconfigured on either side of a rotor 15. The stator comprises a firstset of stator stacks 28-28″ configured on a first side 51 of the rotor15 and a second set of stator stacks configured on a second side 52 ofthe rotor. The tape 30 is shown formed into a stator 12 having aplurality of teeth 26. A return 18 (not shown) is configured inside thecoil 16 and magnetically couples a first stator half 20 on a first side51 of the rotor with a second stator half 22 on the second side 52 ofthe rotor. This stator has a tooth removed from each phase side toprovide for wire area. The rotor is comprises of an assembly of magnets90 and flux concentrators 91.

FIG. 2 shows a side view of the motor 10 shown in FIG. 1. Three statorstacks 28-28″ are configured on either side of the rotor 15 to conductflux from the rotor through a first stator half 20, through the returnand to a second stator half 22 on an opposing side of the rotor. Thereturn coil is configured to extend between a first stator half and asecond stator half. The return coil is configured on the inside diameterof the rotor Rdi as shown in FIGS. 1 and 2, however, a return and coilcould be configured on the outside diameter Rdo of the rotor. The rotorshown in FIGS. 1 and 2 is a ring having an inside and outside diameter,Rdi, Rdo respectively as shown. Again, the figure shows a tooth fromeach phase half removed to accommodate wire.

FIG. 3 shows a cross-sectional view taken along line AA of the exemplarytransverse flux motor 10 shown in FIG. 2. The cross-section shows afirst stator half 20 configured adjacent the first side 51 of the rotor15 and a second stator half 22 configured adjacent the second side 52 ofthe rotor 15. The return 18 is shown configured on the inside diameterof the rotor 15 and within the coil 16. The coil is looped around thereturn as depicted by the two sections of the Coil 16, 16′ in FIG. 3.The return is depicted as a tape in FIG. 3, but could be any suitablemagnetic flux conducting material. The stator magnetic portion as shownin FIG. 3 consist of tape, whereby the first stator half, second statorhalf and the return all consist of tape, as described herein. In someembodiments, one or more of the stator halves may be attached to thereturn such as by being pressed together or through the use of anadhesive. As shown in FIG. 3 both the first and second stator halves 20.22 are attached to the return 18. The width Wt of the stator half ortape is shown in FIG. 3. The control of tolerances may be more easilycontrolled by a slit ribbon that is configured as a stator as opposed toa plurality of parts that require assembly to form a stator and where“tolerance stack-up” occurs. In addition, the tape may be flexible alongthe length of the ribbon but has considerably strength and is rigid in aplane perpendicular to the tape length, or the axial direction.

As shown in FIG. 3, the flux alternates through the coil 16. It passesfrom the rotor 15, through ribbon edge 31, through the first stator half20, out of the first stator half edge 31 and into the return 18 firstedge 94, out the second ribbon edge 96, into the second stator half edge99, into the second stator half 22, and finally back to the rotor 5through the second stator half edge 99. The flux in this embodimentflows substantially along the plane of the ribbons and does not requireflux to flow through the planes or from plane to plane. Again, themagnetic loop may be configured on the outside of the rotor versus theinside of the rotor as shown in FIG. 3.

As shown in FIG. 4A, an exemplary tape 30 comprises a plurality ofribbon layers 36. The edges of the individual ribbon layers make up thetape edge 31. As shown in FIG. 4B an exemplary tape 30 comprises aspacer 32 between the plurality of ribbon layers 36. This may be air asfrom spacing or packing factor, or spacer may be magnetically conductiveor a non-magnetically conductive material such as an adhesive applied indiscrete locations on the tape, such as between ribbon layers or to theouter and/or inner layer of the ribbon. The thickness Tt of the tape 30is shown in FIGS. 4A and 4B and may be any suitable thickness asdescribed herein. A single ribbon 36 is shown in FIG. 5 with the singleribbon edge 37. The thickness T1 of single ribbon layer 36 is shown inFIG. 5 and may be very thin as described herein.

As shown in FIG. 6, an exemplary tape 30 or tape loop 34 is configuredon a core 35. As described, a thin layer of magnetically conductivematerial may be slit and taken-up on a core. The leading and or trailingend of the ribbon may he adhered to secure the ribbon layer to the loop.As shown in FIG. 7A an exemplary tape loop 34 has been removed from thecore 35 and may be flexible and bend easily along the length of theloop, or about the circumference of the loop. The tape loop 34 shown inFIG. 7A may be compressed to the point that the inside surface of thetape loop contact each other and the compressed tape loop takes on theshape of a length of tape.

As shown in FIG. 7B, a tape loop 34 may be slit or a plurality of ribbonlayers may be stacked to form a tape 30 as shown in FIG. 7B. The lengthof an tape may be any suitable length Lt, as shown in FIG. 7B. The tape30 shown in FIG. 7A is a tape loop, whereas the tape 30 shown in FIG. 7Bis a discrete tape, having a length between a first and second end.

As shown in FIG. 8, an exemplary tape loop 34 is formed into a statorstack 28 having a plurality of stator teeth 26 formed from pleated tape.The tape pleat 38 shown in FIG. 8 comprises portions of the tape foldedtogether with the inside tape loop 34 surface 40 contacting along theinside of the fold. The inside surface 40 does not however have tocontact to form a pleat or tooth. The tape loop 34 shown in FIG. 8comprises a first portion 44 of the tape configured as pleats, or statorteeth 26, and the remaining portion of the tape loop, or second portion45 configured between a first end and second end of pleated portion ofthe tape. In another embodiment, a tape 30 is formed into pleats 38, orteeth with no second portion between the first and second end of thepleated tape as shown in FIG. 9. It is to be understood that acompressed tape loop may be formed into as stator half as shown in FIG.9 with the entire tape loop pleated, thereby not having a second portionof the tape loop connecting the first and second end of the a pleatedportion; the entire tape loop would be formed as one piece.

As shown in FIG. 9, an exemplary tape 30 is formed into a stator 28having a plurality of stator teeth 26 formed from a discrete tape 30. Atape loop may he cut to form a discrete tape as shown in FIG. 9. Thetape ends 39 of the tape shown in FIG. 9 are not in an area that willaffect the tolerances. The tape ends may be adhered to the formed tape.The stator 28 comprises a tooth fold 46 and a return fold 48 and may hefolded to any suitable fold angle, Fa.

A fold angle Fa is the angle measured from a line extendingsubstantially parallel with a surface on one side of a fold, to a lineextending substantially parallel with the same surface of the tape onthe opposing side of as fold as shown in FIG. 9 and FIG. 10. The rotorfolds 46 shown in FIG. 9 would have a fold angle of substantially 180degrees since the inside surface of the tape touches along the rotorfold.

As shown in FIG. 10 an exemplary tape 30 is formed into a stator stack28 having a plurality of stator teeth 26 formed from pleated tape. Thestator stack 28 shown in FIG. 0 is formed from a discrete length of tape30 and the inside surface does not contact along the inside oldiepleats. This type of pleat may be referred to as a saw tooth type pleat.The fold angle Ea of this type of pleat is less than the fold angle ofthe rotor folds shown in FIG. 9. A sinusoidal pleat having a sinusoidalshape may also he employed in the formation of a stator stack. Each ofthe teeth shown in FIG. 9 comprises a gap within the pleat of the tooth.This gap may reduce losses.

As shown in FIG. 11, a portion an exemplary in-plane three phase 70transverse flux motor 10 comprises stator halves of formed tapeconfigured on either side of a rotor 15. FIG. 11 shows angling of theinner porting of the teeth such that clearance for the wire may heprovided for without reducing teeth or flux area. The motor is anin-plane three-phase motor type 70 having three stators 28, 28′, 28″ onboth the first rotor side 51 and second rotor side 52. These stators maybe identical or not depending on design and manufacturing requirements.Each stator magnetic portion comprises a first stator half 20 and secondstator half 22 and a return (not clearly shown). The cod 16 in thisembodiment is configured around the return and between the first statortooth 26, or first pole of that phase, and the last stator tooth 26″, orlast pole of the phase, and does not follow the contour of the rotor asshown in FIG. 1. In addition, the stator halves are configured with coilentry ends 62, whereby the coil may enter without the loss of a statortooth or active pole. The rotor and/or return folds at the coil entryend 62 may be different from the rotor and/or return folds throughoutthe rest of the stator half, and may he different by any suitable degreeincluding more than about 10 degrees, more than about 30 degrees, morethan about 45 degrees, more than about 60 degrees, more than about 90degrees and the any suitable range between and including the valuesprovided.

FIG. 12 shows the exemplary in-plane three phase transverse flux motor70 shown in

FIG. 11, in an exploded view, whereby each of the components of thestator magnetic portion are shown including the first stator half 20,return 18 and second stator half 22. A return may comprise one or moreportions such as 18 and 18 as shown in FIG. 12 or combining 18 and 18′into 1 part. The coil entry ends 26 are more clearly shown in FIG. 12 aswell.

FIG. 13 shows a side \dew of the exemplary in-plane three phasetransverse flux motor 70 shown in FIG. 11. As shown in FIG. 13 theexemplary transverse flux motor 10 comprises three stators, 28-28″formed from tape. Note the stator teeth are slightly offset to the polesor rotor switching surfaces to reduce cogging and noise. This is anasymmetric stator 60 configuration as described herein. The suitor isconfigured as if there are 121 poles in the rotor however there are only20 poles. In addition, the first stator tooth 26 and last stator tooth26′ of the stator 28 are configured to allow for the entry of the coilwithout the loss of a tooth and useful pole, in a coil entry end 62configuration. This configuration increases the power and efficiency ofthe motor.

As shown in 14 an exemplary stator half consists of formed tape 30. Thetape comprises a plurality of folds 33, 33. Fold 33 is an inside fold,where the inside surfaces of the tape are folded together or towardseach other. Fold 33′ is an outside fold, where the outside surfaces ofthe tape are folded together or towards each other. A stator maycomprise any number of inside and outside folds, and each fold may haveany suitable fold angle Fa, as described herein A tape withsubstantially a 180 degree fold angle is folded back upon itself suchthat the tape on one side of the fold is substantially aligned with thetape on the other side of the fold. Also shown in FIG. 14 are the tapeends 39, and 39′. The tape ends are not located in an area that wouldcause any flux flow disturbance or loss. FIG. 14 shows the inner portingof the teeth angling in to the return such that the space requirementsfor the coil (not shown) have clearance without losing a tooth andreducing flux area.

As shown in FIG. 15, a portion an exemplary double in-plane three phase74 transverse flux motor 10 comprises stator halves of formed tapeconfigured on either side of two rotors 15, 15. The coil 16 extendsalong each stator and has a coil end turn 65, whereby the coil iselectrically continues with a coil extending along the adjacent stator.Very high utilization of the coil is achieved, with this design withonly the coil connector not being effectively engaged in powergeneration.

As shown in FIG. 16, a portion an exemplary axially-stacked three-phasetransverse flux motor 76 having tape stator halves configured on eitherside of as rotor of three rotors 15-15″. The stator halves 20, 22 extendsubstantially around the entire rotor 15, as shown in FIG. 16.

FIG. 17 shows an isometric view of a portion an exemplary single-phasetransverse flux motor 78 having a tape 30 stator 28 configured on eitherside of is rotor. A first stator half 20 and second stator half 22extend substantially all the way around the rotor 1 5. The stator halvescomprises coil entry ends 62, 62, whereby the coil contacts may extendaway from the coil and outside of the stator 28. This stator isconfigured as an asymmetric stator 60 whereby the stator teeth 26 areexemplarily aligned for 121 poles and there are only 120 poles.

As shown in FIG. 18, an axial transverse flux motor 70, comprises aplurality of discrete stator teeth 26-26′, also referred to as poles,configured on either side of the rotor 15. The discrete stator teeth areflattened tape wound toroids that are made out of separate pieces ofmaterial from each other. Each discrete stator tooth comprises as gap 94which reduces the tendency of flux to pass through the planes of thetape which would cause additional loss. The return 18 providesmechanical support and transfers flux from a first tooth on a first sideof the rotor to a second tooth on a second side of the rotor. The rotor15 is comprises of magnets 90, 90′ and flux concentrators 91 disposebetween magnets. The magnets extend further radially than the fluxconcentrators 91, as shown. In an exemplary embodiment, the magnets 90extend further inward, further toward the center of the motor, than theflux concentrators 91 Only as portion of the stator, two teeth per side,are shown in FIG. 18 to allow more clear depiction of the components.

As shown in FIG. 19, a multiphase arrangement where flux is sharedrather than having discrete phases axially as shown in FIG. 16. Eachstator stack 24 comprises 30 discrete stator teeth 26 configuredradially. Each tooth, or pole, is made of a flatted tape wound toroid.The teeth are positioned around the toroid return. The return shown is atoroid of wound tape. The axial transverse flux motor 70 comprises threephases with one rotor per phase. Only four stator stack make up thethree phase assembly. Each phase only require one additional statorstack, whereas prior requires two stator stacks generally spaced apartper Phase. Therefore, this motor design provides for better efficiency,smaller size and lower weight! Or a given output. Each rotor 15comprises a magnet 90 and flux concentrator 91.

FIG. 20 shows the electrical output from the three phases of the motorshown in 19. It can be seen that although there are some differencesfrom phase to phase they can be essentially the same as three discreteand spaced single phased motors, as shown in FIG. 16.

FIG. 21 shows the data used to produce the graph shown in FIG. 20. Anapproximately +/−2% variation in voltage between phases occurs. Smallrefinements may be required for some applications. The variations shownmay also be remnants of modeling inaccuracy, such as those caused bymeshing choices.

Definitions

Tape, as used herein, is defined as a plurality of slit magneticallyconducting ribbons configured one on top of another. A tape may be atape loop wherein it is essentially continuous, or discrete having alength between a first and second end. A tape or ribbon may have anysuitable thickness.

Magnetically couple, as used herein, means that magnetic flux can flowfrom one material to another. A material that magnetically couples afirst article to a second article conducts magnetic flux from the firstarticle and to the second article.

Teeth or a tooth, as used herein, is a pole when configured. In anelectric motor or generator.

A stator, as used herein, maybe fixed, pivot or rotate or move.

An armature, as used herein, maybe fixed, pivot or rotate or move.

A rotor, as used herein, maybe fixed, pivot or rotate or move.

A pole or pole piece as used herein refers a stator tooth.

It will be apparent to those skilled in the art that variousmodifications, combinations and variations can be made in the presentinvention without departing from the spirit or scope of the invention.Specific embodiments, features and elements described herein may bemodified, and/or combined in any suitable manner. Thus, it is intendedthat the present invention cover the modifications, combinations andvariations of this invention provided they conic within the scope of theappended claims and their equivalents.

What is claimed is:
 1. A stator comprising: a. a tape comprising: i. aplurality of ribbon layers of flux conducting material; b. a pluralityof stator teeth comprising; i. formed portions of said tape; whereby theedge of the tape is adjacent a rotor and configured to conduct magneticflux from the rotor.